So we cosleep with both our kids. We love it and intend on continuing cosleeping for a while. Dave always sleeps on the left side of the bed, with Lacy next to him. Rose and I switch places on the right side of the bed, usually nursing several times in the night, and often she ends up in the middle because out of instinct I put her there-- my instinct doesn't want her falling out of bed!
Last night, well, I didn't really sleep too well. Miss Rose decided to keep pushing and pushing and pushing. I ended up with about a foot of bed space. Lacy also pushed Dave closer to the edge, but at least his whole body was in bed. So when Rose woke me up this morning, I noticed there was about 3 or 4 feet of empty bed in the middle!
No wonder I'm sore!